Drug lord Pablo Escobar, who headed a viscous group of cocaine traffickers in Columbia, once owned four hippopotamuses, which lived in his yard. Escobar died in 1993, but the large mammals outlived their owner, and began breeding. Today, the animals -- and their descendants -- are becoming an invasive species.
Pablo Escobar built a zoo for his son, while the drug lord was at the peak of his power in the 1980's. His ranch, Hacienda Napoles, located in Puerto Triunfo, was home to several animals. In addition to the hippos, the land also contained giraffes and elephants.
The drug lord was gunned down by police 21 years ago, and the hacienda was turned into a park. Many other animals were sent to zoos, but the hippos remained on the property. Local officials took over control of the park, and the giant animals started to breed. Now, there are between 50 and 60 members of the species in the park, and they are starting to move outside the property, where they are encountering locals.
"They found a creature in a river that they had never seen before, with small ears and a really big mouth. The fishermen, they were all saying, 'How come there's a hippo here?' " Carlos Valderrama, a conservationist with the local group Webconserva, told the BBC.
Hippopotamuses present several dangers to humans and animals, and are responsible for between 100 and 200 human deaths each year. Like all invasive species, they also pose a hazard to biodiversity in the region where they travel.
Authorities are uncertain what to do about the problem. Collecting all the animals and moving them to a specially-constructed park would cost an estimated $500,000. Many environmentalists believe that money would be better-spent on protecting native species. They can't be shipped to Africa, where they are native, for fear they could carry disease.
Some local zoos have adopted hippo babies, but the adults are still roaming free on the drug lord's former property. None of the facilities are interested in taking the older animals.
In Africa, droughts help keep hippopotamus populations under control. The area where the animals are now becoming invasive is largely immune from long periods without rain. This adds to the number of hippos being born. Male hippopotamuses normally start breeding at age seven, and females around two years later. In the near-ideal conditions, the animals are starting to mate when they are just three years old.
Columbia is still recovering in many ways from Escobar's reign of terror. The hippopotamus is another example of how his presence is still being felt today.